gitk: Update copyright dates

Signed-off-by: Paul Mackerras <paulus@samba.org>

gitk

@@ -2,7 +2,7 @@
 # Tcl ignores the next line -*- tcl -*- \
 exec wish "$0" -- "$@"
 
-# Copyright © 2005-2011 Paul Mackerras.  All rights reserved.
+# Copyright © 2005-2014 Paul Mackerras.  All rights reserved.
 # This program is free software; it may be used, copied, modified
 # and distributed under the terms of the GNU General Public Licence,
 # either version 2, or (at your option) any later version.
@@ -2947,7 +2947,7 @@ proc about {} {
     message $w.m -text [mc "
 Gitk - a commit viewer for git
 
-Copyright \u00a9 2005-2011 Paul Mackerras
+Copyright \u00a9 2005-2014 Paul Mackerras
 
 Use and redistribute under the terms of the GNU General Public License"] \
 	    -justify center -aspect 400 -border 2 -bg white -relief groove